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1.
采用独特的形核-刻蚀-生长-刻蚀-生长…循环沉积工艺,用微波等离子体化学气相沉积(MWPCVD)法制备出了高纯、高度[100]择优取向的金刚石薄膜.SEM和XRD分析表明得到的膜材具有很高的[100]择优取向性;Raman光谱和SEM对照分析证实膜材的金刚石相组成纯净度高,是高纯、高度[100]择优取向的织构金刚石薄膜.暗电流I-V特性测试结果表明,这种薄膜的电阻率达到1014数量级以上,比常规工艺制备的膜高近两个数量级,是一种性能优良的电子薄膜材料.理论分析表明,薄膜电阻率大幅度提高的原因在于膜层中非金刚石相含量的显著减少.  相似文献   

2.
采用独特的形核-刻蚀-生长-刻蚀-生长…循环沉积工艺,用微波等离子体化学气相沉积(MWPCVD)法制备出了高纯、高度[100]择优取向的金刚石薄膜。SEM和XRD分析表明得到的膜材具有很高的[100]择优取向性;Raman光谱和SEM对照分析证实膜材的金刚石相组成纯净度高,是高纯、高度[100]择优取向的织构金刚石薄膜。暗电流Ⅰ-Ⅴ特性测试结果表明,这种薄膜的电阻率达到10H数量级以上,比常规工艺制备的膜高近两个数量级,是一种性能优良的电子薄膜材料。理论分析表明,薄膜电阻率大幅度提高的原因在于膜层中非金刚石相含量的显著减少。  相似文献   

3.
《中国贵金属》2006,(5):48-49
近期,国际贵金属市场保持了强劲的上升势头,黄金、白银等贵金属价格不断走高,引来众多投资者的关注,为此,《中国财经报道》栏目将就黄金的投资及市场预期采访成都高赛尔黄金分析师杨易君先生。  相似文献   

4.
《Acta Materialia》2003,51(13):3951-3963
A complete classification of [100] tilt grain boundaries into the categories of special, vicinal and general resulting from measurements of grain boundary segregation in α-iron is presented. In contrast to the coincidence site lattice approach at least one special grain boundary was found to exist for each misorientation of adjoining grains irrespective of the value of the reciprocal density of coincidence lattice sites. This finding raises a new challenge to grain boundary engineering. It is suggested that a configuration of typically brittle general boundaries in a polycrystal can be transformed into another one consisting of non-brittle special boundaries under suitable annealing conditions by boundary inclination via boundary migration without any change of grain orientations.  相似文献   

5.
1 INTRODUCTIONBasicityofaslagisoneofoldandimportanttop icsin physicalchemistry .Thereisnostandardfor mulationforbasicitycalculation .Ingeneral,basicityofaslagisexpressedbythemassratioofCaOtoSiO2ortotalalkalineoxidestototalacidicoxides .Accord ingtotheiontheoryofslag ,basicityofaslagshouldbeexpressedbytheactivityofoxygenion ,whichisdifficulttodetermine .Frombasicity principle pro posedbyWagnerandotherinvestigators[15] ,basicityofaslagisproportionaltoitssulfidecapacity .Rela tionshipbet…  相似文献   

6.
7.
《Acta Materialia》2000,48(11):2837-2842
The boundary energies of Σ11 [110] asymmetric tilt boundaries with a misorientation angle of θ=50.5° in Cu have been experimentally determined by a silica particle observation method for various inclination angles between φ=0 and 90°. This method has no drawbacks that are inevitable in boundary grooving and tri-junction methods. In the boundary energy vs inclination angle diagram, three deep cusps exist at φ=10, 64.8 and 90° whereas a shallow cusp appears at φ=35.3°. Such inclination angle dependence of the boundary energy has been utilized to analyze the faceting of the boundary. The observations on the faceting reported for Σ11 [110] tilt boundaries in face-centered cubic (f.c.c.) metals have been quantitatively accounted for by the present analysis.  相似文献   

8.
[FePt/Ag]n multilayers were deposited on glass substrates by RF magnetron sputtering and ex situ annealed at 550℃ for 30 min. The effects of inserted Ag layer thickness and the number of bilayer repetitions (n) on the structure and magnetic properties of the multilayers were investigated. It was found that the difference between in-plane and out-of-plane coercivities varied with an increase of inserted Ag layer thickness in the [FePt 2 nm/Ag x nm]10 multilayers. The ratio of out-of-plane coercivity to in-plane coercivity reached the maximum value with the Ag layer thickness of 5 nm, indicating that the Ag layer thickness plays an important role in obtaining perpendicular orientation. For the [FePt 2 nm/Ag 5 um]n multilayers, perpendicular orientation is also influenced by n. The maximum value of the ratio of out-of-plane coercivity to in-plane coercivity appeared when n was given as 8. It was found that the [FePt 2 nm/Ag 5 nm]8 had a high perpendicular coercivity of 520 kA/m and a low in-plane one of 88 kA/m, which shows a strong perpendicular anisotropy.  相似文献   

9.
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11.
The synthesis and crystal smacture of an polyoxometalate-based organic-inorganic complex [Cu(DMF)3(H2O)212[SiMo12O40].2H2O (DMF = N, N-dimethyl formamide) is described in this article. It was characterized using elemental analysis, thermal analysis, infrared, ultraviolet, and electron spin resonance spectroscopic studies. The X-ray crystallography analysis showed that the copper centers are pentacoordinated to show the square pyramidal geometry, and the polyanion [SiMo12O40]4- which is semi-coordinated to the copper(I/) centers prevents the existence of a sixth ligand. In addition, the intracationic hydrogen interaction enhanced the stability of the copper coordination cation.  相似文献   

12.
江敦润  王锦芬 《贵金属》1997,18(4):16-19
用一种新的合成方法,将钯进行预处理,使其表面活性增大,然后溶入冰醋酸中得到浅棕色结晶,回收率接近100%,用元素分析,红外光谱,紫外光谱、DTA-TG等对产品进行了表征,结果与文献报道一致。工艺操作简单,回收率稳定,未发现粉红色多聚物,可批量生产。  相似文献   

13.
《Synthetic Metals》1998,96(3):199-204
The synthesis, structural characterization and electrical conductivity measurement of [MDA]2[Pd(dmit)2] (1 and [MDA] [Pd(dmit)2]2 (2) (MDA = 2-dimethylamino-1,3-dithiolanylium, dmit = 1,3-dithiole-2-thione-4,5-dithiolate) are reported. Complex 1 consists of two Pd(dmit)2 anions and four MDA cations in the unit cell and the anions are separated by cations in the crystal; the conductivity is about 10−7 S cm−1. The structure of complex 2 is made of stacked Pd(dmit)2 dimers. The modes of intra- and inter-dimer molecular overlapping are both of slide-away types. Pd atoms deviate from planes formed by four ligand S atoms 0.07 Å apart to approach each other. Room-temperature conductivity is 10–70 S cm−1. Temperature-dependent conductivity measurement of this compound indicated that it is a semiconductor with a low activation energy (0.043 eV).  相似文献   

14.
[Pt(en)(5-Fu)2]Cl2配合物的合成及抗肿瘤活性   总被引:1,自引:0,他引:1  
为寻求高效低毒的新型顺铂类抗肿瘤药物,用K2PtCl4、乙二胺(en)、氟尿嘧啶(5-Fu)为原料,设计合成了顺铂类似物[Pt(en))(5-Fu)2]Cl2配合物,由元素分析、红外光谱和质谱分析初步证实了其化学结构,用改良MTT、SRB法,选用K562、A549、Bel-7402、BIU-87、Bcap-37细胞株对其进行体外抗肿瘤活性测定。结果表明,所合成的配合物除在浓度为0.01、0.1/μg/mL时对K562细胞株抗肿瘤活性大于顺铂和氟尿嘧啶外,其它情况下的抗肿瘤活性均小于顺铂和氟尿嘧啶。该配合物仍有进一步研究的价值。  相似文献   

15.
The crystal and molecular structures of the K[TbⅢ(edta)(H2O)3]-5H2O (edta = ethylenediaminetetraacetic acid) and K4[TbⅢ2(Httha)2]+14H2O (ttha = triethylenetetraminehexaacetic acid) complexes have been determined by sin-gle-crystal X-ray diffraction analyses. The crystal of the K[TbⅢ(edta)(H2O)3]·5H2O complex belongs to orthorhombic crys-tal system and Fdd2 space group. The crystal data are as follows: a = 1.9373(5) nm, b = 3.5429(10) nm, c = 1.2114(3) nm, V = 8.315(4) nm3, Z= 16, M = 630.35, Dc = 2.014 g cn-3, m = 3.683 mm-1 and F(000) = 5024. The final R and wR values are 0.0224 and 0.0557 for 3189 [I> 2.0o(I)] unique reflections, and 0.0245 and 0.0567 for all 8206 reflections, respectively. The [TbⅢ(edta)(H2O)3]- complex anion has a nine-coordinated pseudo-monocapped square antiprismatic structure in which the nine coordinate atoms, two N and seven O come from one edta ligand and three water molecules. The crystal of the K4[TbⅢ2(Httha)2]·14H2O complex belongs to monoclinic system and P2(1)/n sp  相似文献   

16.
目的研究超声功率对镀层表面形貌和镀层耐蚀性的影响。方法采用[Bmim]OTf-Zn Cl2-PC离子液体,利用超声电沉积方法,在铜电极表面沉积金属锌。利用电化学工作站考察阴极极化曲线以及镀层的耐蚀性能,测定镀层的电沉积速度。利用扫描电镜分析镀层的表面形貌,显微维氏硬度计测定镀层的硬度,考查超声波功率对镀层性能的影响。结果加入超声波后,金属的还原电位发生正移,镀层的沉积速度从无超声波作用时的4.652 g/(m~2·min)下降到2.146 g/(m~2·min),镀层表面均匀、致密,结合力强,表面硬度从无超声波作用时的185HV增加至251HV。根据Tafel直线外推法得出镀层的腐蚀电位从-1.14 V增加到-0.62 V,腐蚀电流密度从8.8μA/cm~2降低到2.3μA/cm~2,镀层的耐蚀性能变好。结论增加超声波功率明显提高镀层的表面质量,粗糙度逐渐变好,镀层耐蚀性有明显增加的趋势。综合考虑超声电沉积锌镀层的最佳超声功率为120 k W·h。  相似文献   

17.
研究了金属钼(Mo)在离子液体1-丁基-1-甲基吡咯烷双(三氟甲磺酰)亚胺盐中([BMP]Tf_2N)的电沉积。采用MoCl_5[BMP]Tf_2N离子液体体系作为电沉积的电解质,测定了不同温度下的伏安曲线(CV)。用恒电位法进行电沉积,沉积物通过扫描电镜(SEM)、能谱(EDS)、透射电镜(TEM)和光电子能谱(XPS)进行了观察和表征。结果表明,在25~120℃的温度范围内,当温度高于100℃时,Mo的电化学还原行为发生明显的变化。在120℃,Pt基板上,–2.2和–2.7V恒电位电沉积均能得到金属态的Mo。其中,–2.2V时得到非晶态的Mo,沉积层平整、无裂纹;–2.7V时得到晶态和非晶态混合的Mo,沉积层有裂纹。而在60℃,Mo(Ⅴ)还原后形成难溶产物以致无法得到Mo(0)。最后,对Mo的电化学还原机理进行了讨论。  相似文献   

18.
1 INTRODUCTIONThereactivityoftheFeS2 (pyrite)surfaceisofparticularimportantintheengineeringapplications ,includingsulfidemineralsflotation[1] ,bioleachingoflow gradechalcopyrite containingore[2 ] ,coal pro cessing ,hydrometallurgy ,environmentalengineer ing ,geochemistry ,andphotovoltaiccell,etc[3] .Es pecially ,anunderstandingofhow pyritesurfacesin teractwithflotationreagentmoleculeswillaidinthedesignofmoreeffectiveflotationsuppressants ,whichwouldeffectivelyseparatethedesirableoresfrom…  相似文献   

19.
采用二氧化硫脲直接还原 [Ag (S2 O3) 2 ]3- 以沉析银 ,实验研究表明 :提高反应体系的酸碱度、温度和添加微量Hg (Ⅱ )离子 ,能明显加快反应速度 ,提高银的还原沉析率。并得到 :在体系温度为 80℃ ,pH =1 3 0 0 ,催化剂Hg (Ⅱ ) =5× 1 0 - 5mol/L时 ,反应1 5min ,银的沉析率为 99 87%  相似文献   

20.
《Synthetic Metals》1996,79(3):201-206
The structure, resistivity and ESR of a new organic conductor κ-ET2[Hg(SCN)2I](ET=bis(ethylenedithio) tetrathiafulvalene) are studied. Its main crystallographic parameters are found to be: M-1213.2, a-38.03(1), b= 11.80(1), c = 8.329(9) Å; γ=98.1(2)°; V-3700(2) Å3; space group P21Ib; Z = 4. It is shown that the radical cations are packed according to the κ-type in the organic sheets, and the anions form polymerized chains. Two different radical cation layers with different amounts of shortened S···S contacts and distinct interaction between anionic and cationic sheets are found. ESR linewidth is found to be 9-11G (300 K), which is substantially narrower than a typical linewidth for ET-based radical cation salts of the κ-type. Based on temperature dependences of the resistance anisotropy and ESR parameters, we suggest that a structure rearrangement with electron localization may take place around 50 K. The comparison of crystal structure and properties of the title compound with other salts of the family ET2[Hg(SCN)3nXn], where X=Cl, Br, and n = 1.2, is camed out.  相似文献   

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